中文摘要：

针对非API套管接头的连接和密封性能提出一套完整的解析评估计算方法。首先建立具有密封和内外螺纹啮合结构的非API套管接头力学分析模型,依据API套管接头失效形式（螺纹跳扣、螺纹剪切破坏和接头断裂）及其机理结合弹塑性力学理论,推导出非API套管接头发生相应连接失效时的临界轴向载荷计算公式。然后,依据螺纹啮合对变形协调方程和单个螺纹牙轴向弹性变形分析,推导出套管接头螺纹牙啮合法向接触力计算方程组,从而获得非API套管接头各个螺纹牙轴向变形量及其承载轴向载荷分布情况数值解。最后,通过对比各个螺纹牙承载轴向载荷与连接失效临界载荷对非API套管接头进行连接性能评估;通过计算轴向载荷和气体内压作用下,套管接头螺纹轴向变形量及其对接头密封过盈配合值的影响,对非API套管接头进行密封性能评估。通过对3种典型非API套管接头完整性评估计算结果表明：在螺距、螺纹啮合中径、螺纹高度等螺纹参数相同情况下,非API套管接头的螺纹牙型设计参数（承载面角度与导向面角度）对其连接和密封性能影响显著。

英文摘要：

An analytical method evaluating the connection and sealing performance of non-API casing connections was proposed in this study. First, a mechanical model addressing the sealing and thread meshing of non-API casing connections was developed. According to various failure modes of API connections, such as thread slipping, shear failure, joint rupture, and the elastic-plastic theory, the formulas calculating critical axial loads for non-API casing connections were derived. Second, a set of equations for calculating the contact stress of casing thread were derived according to the deformation compatibility of the meshing thread teeth and the axial deformation of the single thread tooth. Subsequently, the axial deformation of the thread teeth and their load distribution values were obtained. Finally, the performance evaluation result for non-API connections was obtained by comparing the thread teeth＇s load with the critical axial load. According to the axial deformation calculation results of the casing connection and its influence on the sealing interference fitted value, the sealing performance evaluation results for non-API connections were derived. The evaluation results for non-API connections of three types showed the thread design parameters had significant effects on the connections and sealing performance for non-API casing connections.